Manufacture of sealed enclosures



June 15, 1954 0355 ETAL 2,681,296

MANUFACTURE OF SEALED ENCLOSURES Filed Aug. 13, 1951 I ELECTRONIC F 7GauetAroz F19 6 JNVENTORS: FRANK 00888 BY .sT Pm/v 0055.:

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Patented June 15, 1954 2,681,296 MANUFACTURE OF SEALED ENCLOSURES FrankG. Dobbs and Stephan H. Dobbs, New York, l Y.

Application August 13, 1951,

4 Claims.

The invention relates to enclosures, and relates more particularly tosealed receptacles, made of flexible sheet material, such as purses,luggage, and the like, and to the manufacture thereof.

The invention has among its objects the provision of sealed receptaclesthat may be made simply and inexpensively, and of methods used for themanufacture thereof.

With the above and other objects of the invention in view, the inventionconsists in the novel methods, as set forth in the claims hereof, anddescribed in the specification.

In the accompanying drawings,

Fig. 1 is a perspective view of a finished receptacle, in accordancewith an embodiment of the invention;

Fig. 2 is a sectional view taken on line 22 of Fig. 1;

Fig. 3 is a sectional view, similar to Fig. 2, illustrating themanufacture of a receptacle of the preceding views, but showing the samein a semi-finished state;

Fig. 4 is an extended perspective view, of the receptacle parts and thetool shown in Fig. 3;

Fig. 5 is a fragmentary sectional view, on an enlarged scale,illustrating the tool shown in Figs. 3 and 4 penetrating into thereceptacle material;

Fig. 6 is a fragmentary sectional view, similar to Fig. 5, but showing amodified tool;

Fig. 7 is a sectional view similar to Figs. 5 and 6, but showing afurther modified tool; and

Fig. 8 is a fragmentary sectional view showing, on the scale of Figs.5-7, the edge of a finished receptacle that was operated on by the toolillustrated in Fig. 7.

In Figs. 1 and 2 there is shown a sealed enclosure structure such as areceptacle -I I. The receptacle II is shown to be of cylindrical shape.

The receptacle II has a top wall I2, a bottom wall I3 that is parallelthereto, and an endless intermediate cylindrical side wall I I. The sidewall 14 has upper edges [6 and lower edges H; the upper edges I6 aresealed to the edges I8 of the top wall I 2, and the lower edges I I aresealed to the edges I9 of the bottom wall I3. These edges all project onthe interior of the receptacle M.

The material of the walls I2, I3 and I4 is thin and flexible sheetmaterial, and is preferably composed either of thermoplastic substance,or of a substance that has otherwise also thermoplastic surfacecharacteristics, for instance due to coating or other treatment for thatpurpose. The sealing, as will be explained in detail later Serial No.241,618

on, is preferably carried preferred embodiment quency heat fusing.

As best shown in Figs. 1-3, the side wall I4 is provided with ahorizontal aperture 2I that may be opened and closed by a slide fastener22. The aperture 2| and the slide fastener 22 extend throughout a largeportion of the circumference of the side wall I4, in order to enableturning inside-out of the receptacle II. During manufacture, the edgesI6, I1, I8 and I9 of the receptacle project on the exterior thereof andthe receptacle is later'on reversed to place the edges on the interior.

The assembling of parts for the manufacture of the receptacle isillustrated in Figs. 3 and 4. The bottom wall I3 is placed on a platen23 that is conductive and is insulated on an insulating support and isinterconnected to a generator 24 for electronic high frequency current.Guides 25 may be provided to position the bottom wall I3 on the platen23.

The side wall I 4 is mounted on an annular tool 26 in such a manner thatits end portions 21 are bent over the upper and lower contours of thetool 25 extending on the outside of said tool. The side wall I4 adheresto the tool 26 owing to this bending of its end portions 27. The tool 26is movable to and from the platen 23 either manually, or by means of aguiding and positioning element 28 that is attached to the exterior ofthe tool at a location that avoids interference with the mounting of theside wall I4 on the tool 26.

After the bottom wall I3 has been positioned onto the upper surface ofthe platen 23 within the orbit of the guides 25, and the wall I i hasbeen mounted on the tool 26, the tool is lowered, until the side wall I4is supported by the bottom wall I3 resting on the platen 23. Thereafter,the top wall I2 is placed over the top of the side wall i l, and aconductive plate 29 is superposed thereon. The plate 29 is movablerelative to the platen 23, for instance by guide means comprising aguide 3|, and is electrically interconnected to the generator 24.

The top wall I2 may either be placed directly onto the side Wall I4, orinstead may be positioned on and carried by the under surface of theplate 29, for instance by means of brackets 32.

The tool 26, as best shown in Fig. 3, comprises a center section 33 thatis preferably made of insulating material and that carries on itsopposite edge portions combined binding and trimming out by heat, and ina by electronic high fremeans. The binding means comprises an annularelectrode 34 on the top of the tool, and an annular electrode 36 on thebottom of the tool. Each of these electrodes is electricallyinterconnected to the generator 24. The trimming means include anannular top cutter 31 and an annular bottom cutter 38, and each cutteris connected to an electrode and, for instance, may be integraltherewith. The end portions of the top electrode 34 and of the topcutter 3i, that are shown in Fig. 3, are illustrated in an enlargeddetail view in Fig. 5.

Instead of using separate electrode and cutter, they may be united toform a single binding and trimming means, such as the modified tool asillustrated in Fig. 6. The tool dB which, like the tool 25, can eitherhave a single or two opposite operating edges, includes a surface 33that is in clined inwardly of the tool and carries out the binding partof the operation, and a substantially straight surface ll thatintersects the inclined surface 39 at the cutting edge 12 for thetrimming part of the operation.

A further embodiment of the tool is in '7. The modified tool 133comprises an electrode 5:1 which is similar to the electrode 3d of 3 and5, and a cutter 4% that is secured to the electrode M and may beintegral therewith. Similar to the earlier described cutter 3'5, themodified cutter 46 projects beyond the free end of the electrode towhich it is attached; however, the cutter 46, furthermore, is offsetlaterally from the end of the electrode M and forms therewith a recessii. The purpose of this recess is illustrated to enable the materialduring the sealing and trimming operation to flow thereinto for forminga ridge at as shown in Fig. 8.

The operation of the apparatus and parts described is as follows.

The bottom walls l2 and is of the receptacle may be formed by stampingor cutting from sheet material. The side wall i l may be cut fromtubular material, or prepared by fusing or other sealing fromrectangular rolled-up sheet material.

he bottom wall i3 is then placed inside the f 1 es 25 on the top surfaceof the platen 23. The side wall Hi is provided with the aperture 2! andthe slide fastener 2'8, and is mounted on the tool 25, the latter havingthe platen 23, and the mounting of the side wall being completed bybending the end portions 21 thereof over the top and bottom contours ofthe tool 25. The top wall i2 is either placed atop the side wall it thatis held on the tool 26 and maintained thereon by its own stiffness, orby spacers lnot shown), or is mounted on the underside of the plate 29by means of the brackets 32 thereon.

The tool 2%, carrying the side wall M, may be lowered in registry ontothe positioned bottom wall it either manually, or be guided intoposition by means of the guide 28. The plate 29 is then guided intoregistry position by the guide 3 i. The top portion of the side wall I lis thus put in lamination superposition with the outer portion of thetop wall 52, and similarly the bottom portion of the side wall M withthe outer portion of t 'ie bottom wall it.

Thereafter, a pressure mechanism (not shown in detail), indicated by thearrow 5!, is actuated to press the plate 29 downwardly in a directiontowards the platen 23. This actuation may be timed with the actuation ofthe generator 24, preferably automatically as is well-known to thosefamiliar with this art.

been moved away from By this pressure movement of the plate 29, theplate 29 and the platen 23 press the end portions of the walls againstthe edges of the tool 25. During this pressure movement, high frequencyelectric current fed from the generator 24 to the plate 29, to theplaten 23 and to the electrodes 34 and 35, will induce heat in the endportions of the sheet material walls l2, l3 and M. The electrodes 3d and3 6 will penetrate into the superposed wall portion laminations adjacentthereto and fuse the same, while the cutters 3"! and 38 will outthroughout a major part of the combined thickness of the assembly ofsuperposed laminations of the wall material.

The pressure movement is so controlled, that it will terminate beforethe cutters 3'5 and 38 completely pierce the laminations. Completepiercing must be avoided, in order to prevent arcing between theelectrode and the plate or platen opposite thereto.

Thereafter, the plate 29 is raised, and the assembled wall enclosurestructure removed from its emplacement in the apparatus. Owing toincomplete piercing of the material by the cutters, the end portions ofthe walls still adhere to the structure. They are thereafter torn off,along the broken lines 52 shown in Figs. 5, 6 and '7, to complete thetear seal operation. Subsequently, the enclosure structure is turnedinside out, by way of the open slide fastener 22, resulting in thefinished receptacle shown in Figs. 1 and 2.

During the pressure movement of the top plate 29, that part of thematerial which is displaced by the entry of the tool edge will form aridge along the sides of tool entry, as shown at 53 and 55 in Figs. 5-7.As shown in Fig. 8, in the immediate vicinity of the electrode thematerial of the laminations will be so fused that it substantiallyunites as illustrated at 56. Opposite the ridge 53 the laminations willbe forced apart forming a narrow cavity 53.

As best shown in Fig. 8, the ridges left by the impression of the tool63 are graceful in appearance while promoting strong wearingcharacteristics of the sealed receptacle.

Reference is being had to our co-pending application, Ser. No. 319,862filed November 12, 1952.

In the preceding description, the apparatus and receptacle are for acylindrical shape. However, rectangular or other shapes lend themselvesequally well for treatment in accordance with the described method andmeans, and the modifications of the wall parts and tool necessarytherefor are within the scope of the invention, save as limited by theclaims hereof, and are simple to design. If necessary, the tool 26 maybe made of more than one part, for instance by uniting several partsthereof, as indicated by bolt and nut assemblies numbered 58 in Fig. 3.

It will be apparent to those skilled in the art that the novelprinciples of the invention disclosed herein in connection with specificexemplifications thereof will suggest various other modifications andapplications of the same. It is accordingly desired that in construingthe breadth of the appended claims they shall not be limited to thespecific exemplifications of the invention described herein.

Having thus described the invention, what we claim as new and desire tobe secured by Letters Eatent, is as follows:

1. In a method of binding and trimming cover material on tubularmaterial, all material having thermoplastic surface characteristics, the

steps comprising, bending the opposite outer endless edges of saidtubular material, superposing on each endless edge a cover, wherebythere will be two multiple layers spaced from each other, each layerbeing disposed near an end of said tubular material, subjecting both ofsaid spaced multiple layers simultaneously to the same pressure and toheat for binding the same, and exerting pressure of the same magnitudeto both layers for cutting simultaneously into the laminations formed bysaid layers to a predetermined fractional layer depth.

2. In a method of binding and trimming two spaced covers of a materialon a piece of material located between said covers, all said materialhaving thermoplastic surface characteristics, the steps comprising,bending outwardly the opposite outer edges of said piece, superposing oneach edge a cover, whereby a cover will form a layer with the outwardturned edge at each end of said piece, said layers being spaced fromeach other for the length of the piece therebetween, applying the sameamount of pressure simultaneously to both layers, and applyingsimultaneously to both layers heat, for binding the laminations of eachlayer, and cutting into each layer to a predetermined fractional layerdepth.

3. In a method, as claimed in claim 2, said piece having tubular form,the application of pressure and heat taking place outside the orbit ofthe tubular material between said layers.

4. in a method of binding and trimming cover material on tubularmaterial, all material having thermoplastic surface characteristics, thesteps comprising, bending the opposite outer endless edges of saidtubular material, superposing on each endless edge a cover, wherebythere will be two multiple layers spaced from each other, each layerbeing disposed near an end of said tubular material, applying pressurefrom the exterior against each layer and simultaneously between saidlayers, whereby both layers will be subjected to the same amount ofpressure as the pressure exerted against one layer is taken up by theother, and applying heat, to bind the lamination of each layer, andcutting through each layer to a predetermined fractional layer depth.

References Cited in the file of thi atent UNITED STATES PATENTS

1. IN A METHOD OF BINDING AND TRIMMING COVER MATERIAL ON TUBULARMATERIAL, ALL MATERIAL HAVING THERMOPLASTIC SURFACE CHARACTERISTICS, THESTEPS COMPRISING, BENDING THE OPPOSITE OUTER ENDLESS EDGES OF SAIDTUBULAR MATERIAL, SUPERPOSING ON EACH ENDLESS EDGE A COVER, WHEREBYTHERE WILL BE TWO MULTIPLE LAYERS SPACED FROM EACH OTHER, EACH LAYERBEING DISPOSED NEAR AN END OF SAID TUBULAR MATERIAL, SUBJECTING BOTH OFSAID SPACED MULTIPLE LAYERS SIMULTANEOUSLY TO THE SAME PRESSURE AND TOHEAT FOR BINDING THE SAME, AND EXERTING PRESSURE OF THE SAME MAGNITUDETO BOTH LAYERS FOR CUTTING SIMULTANEOUSLY INTO THE LAMINATIONS FORMED BYSAID LAYERS TO A PREDETERMINED FRACTIONAL LAYER DEPTH.